A patch for graphViz4Matlab toolbox

This is a patch for graphViz4Matlab toolbox (version April 24, 2010).

This patch enables automatic change in thickness and also color of the graph edges (for now, gray level coloring).
It also disactivates the box and visibility of the axes in order to facilitate removal of the white
spaces around the graphs using "Remove white space around images" function
(http://www.mathworks.com/matlabcentral/fileexchange/34898-remove-white-space-around-images).

To apply this patch:
1. Install graphViz4Matlab and graphViz as described in
graphViz4Matlab documentation (http://www.mathworks.com/matlabcentral/fileexchange/21652-graphviz4matlab) or the following link: http://code.google.com/p/graphviz4matlab/

2. Copy/Overwrite graphViz4MatlabNode.m to the root subfolder of graphViz4Matlab toolbox

3. Copy/Overwrite graphViz4MatlabNode.m to the "util" subfolder of graphViz4Matlab toolbox

4. Done!